New mesocarnivore at the doorstep of Central Europe: historic development of golden jackal (Canis aureus) population in Slovenia

Abstract

Golden jackal (Canis aureus) has dramatically increased its distribution and abundance in Europe. Expansion is now reaching parts of Central, Northern, and Western Europe, where jackal occurrences are mainly limited to vagrants or single territorial groups. Currently, it is hard to predict future development of jackal populations in these regions, as it remains unclear whether environmental conditions here could enable population growth similar to the jackal core areas in the South-eastern Europe. We used a combination of a literature review, opportunistically collected data and systematic acoustic surveys to study historic development of golden jackal population in Slovenia, a Central European country that jackals started colonizing 70 years ago and which could serve as a model for other countries at the expansion frontier due to its resemblance in environmental conditions. After the initial expansion waves reached Slovenia in the 1950s and 1980s, jackal presence became more permanent since 2000s. This is also the period when first territorial groups and reproductions were confirmed, but it was not until the following decade for the number of records to start exhibiting an exponential growth. By 2016–2017, the minimum densities in lowlands reached 0.06–0.29 jackal territorial groups/10 km2, which is still lower compared to the core areas in the Balkans and the Pannonian Basin. This study demonstrates that jackals can successfully colonize and spread across a forested Central-European country with lower availability of anthropogenic food resources, although in such conditions, it can take several decades of sporadic existence before population progresses into exponential growth similar to jackal populations in the European core areas.